A New Jersey casino has sued a group of gamblers who won $1.5 million after they allegedly realized the eight decks of cards used in a game of mini baccarat were not preshuffled.

The Golden Nugget in Atlantic City, N.J., filed suit against the gamblers and playing card company Gemaco after 14 players collectively won $1,536,700 in 41 winning hands.

As the same sequence of cards kept appearing April 30, the players increased their bets from $10 to $5,000, the casino alleged.

"The gamblers unlawfully took advantage of the Golden Nugget when they caught onto the pattern and ... by passing money to fellow gamblers in order to place bets in excess of posted betting limits," the casino said in a statement.

In a lawsuit filed in New Jersey Superior Court, the casino cited gambling regulations that state gaming odds must be fair for both sides.

The Golden Nugget is seeking a return of the $558,900 it paid out to several of the players and the nearly $1 million worth of chips.

Benjamin Dash, attorney for the gamblers, said his clients, who did not know each other, were "playing the game lawfully."

After paying out a portion of the winnings, the casino managers became suspicious. Convinced they were watching a "sophisticated swindling and cheating scheme," they refused to cash in the remaining $1 million in chips.

No evidence of a scheme was found. On May 1, the Golden Nugget said it learned by "direct admission" from Gemaco's CEO that the decks used in the baccarat game were unshuffled, despite being touted as preshuffled, certified decks.

ABCNews.com was unable to reach Gemaco for comment.

Three of the gamblers filed a countersuit against the casino alleging they were discriminated against because of their Chinese heritage.

"All of the players were Asian [and] none of their chips were honored," Dash said. "In New Jersey, a chip is evidence of a debt."

After the win, Dash said, one of his clients was assaulted when he answered the door of his hotel room.

The man was pinned against a wall and his belongings were searched, Dash said. He was then held in a room without access to food, water or an interpreter, according to allegations in the countersuit, which identifies no particular assailant.

The Golden Nugget called the claims "completely false."

"[We] would never discriminate against anyone, including the Asian community," the casino said in a statement. "In fact, the Golden Nugget designed and built an Asian gaming area and restaurant to specifically attract Asian guests to the casino."